Improvement in railway-car brakes



l.. RADDIN.

yRailway Car-Brakes. No.l47,57l. e .PatentedFeb.17,1s74.

the shafts by the hand-wheels.

UNITED STATES PATENT OFFICE JOHN nAnniN, on LYNN, MASSACHUSETTS.

Vlli/IPRovEMianl'lf IN RAILWAY-CAR BRAKES.

Specification forming part of Letters Patent No. 147,571, dated February17, 1874; application tiled November 3, 1871.

` Mechanism for Railway-Gars; and I do hereby declare that thefollowing, taken in connection c with the drawings which accompany andform part of this specification, is a description of my inventionsufficient to enable those skilled in the art to practice it. v

This invention relates to the construction and arrangement of asafety-brake mechanism for railway-cars.

Ordinarily, as is well known, brakes are applied to the wheels of carsby drawing the brake-spurs to thewheel-peripheries by brakelevers, rods,and chains, the chains being woundby the brakeman upon the windlasses orshafts of the hand-turned wheels at the end platforms of the cars. Whenreleased from strain, the chains unwind and the brakes loosen their holdupon the wheels, suitable springs throwing them back from thewheel-peripheries. By such method of applying and operr ating brakes,much time is always consumed in operating the brakes, or in starting tooperlate them when a train is to be quickly arrested. To obviate this, amechanismhas been devised by which, by means 'of coiled springs placedon the windlass or chaii'i-winding shafts, the brakes are applied by thestress of springs, and are thrown from the wheels by turning For reasonsnot necessary herein to mention, such brake mechanism'has provedimpractical, and is not now in use, return having been made to thesimpler brakes brought into action by hand.

In my invention, I have sought to devise a simple but reliableorganization by which the brakes should be automatically thrown againstthe wheels, and should be drawn therefrom by hand, instead of beingapplied by hand, and springing from the wheels when the windlasses arereleased. For this purpose I hang each brake-fra1ne at the outer end ofthe cartruek, and connect the cross bars or beams (to which the brakesare fastened) together by strong contractile springs, the stress ofwhich shall draw the brake-shoes tightly against the wheels, so thatwhen thc sprin gs are free thus to operate the brakes, the friction ofthe brakeshoes upon the wheels shall be sufficient toarrest the car inthe shortest space of time or length of distance in which it ispractical to arrest a car by pressure upon the Wheels, the length oftime or space being, of course, dependent upon the speed at which thecar may be ruiming. Of course the pressure must not be sufficient tolock the wheels or cause them to slide, and there may be mechanismcombined with the springs for increasing or lessening their stress. Thepressure may be induced by weights acting directly on the brakeframes;but this is not so practical as the springs, they being more eficientfor the purpose. rEhe brakes so operated are connected, by suitablerods, chains, and levers, with the brake-windlass, and this mechanismbeing so arranged that the springs are expanded and the brakes drawnfrom the wheels by winding the chains upon the windlass-shafts, suitableratchet-and-pawl mechanism being employed to hold the brake-frames inposition. It is in this method of operating brakes that my inventionconsists.

The drawing represents in reverse plan and in side elevation a car-truckandplatform embodying the invention.

a denotesthe truck-frame; b b, c c, the two pairs of wheels; d c, theaxles journaled in suitable boxes, the truck, wheels, axles, boxes, andhousings being constructed and arranged in the ordinary manner. h idenote two brake bars or rails, to the inner sides of which the brakes kk l l are fixed, the brake bars or rails being hung from the end rails mof the truckframe a, and so that the brakes can swing freely against orfrom the wheels. To the two ends of the two brake-frames, at each sideof the truck, the opposite ends of a spring, n or o, are fastened orconnected, each spring being preferably a long coiled contractilespring, the stress of which tends to draw inward the brake-frames and toforce the brakes against the wheels, and producing such action of thebrakes whenever the brakes are at liberty to so move against the wheels.Each brakeframe is connected, by rods pq, levers r, and chains s, with awinding-shaft, t, upon the top of which, above the platform u, is ahandreleasing the ratchet from it, the stress of the springs willimmediately throw the brakes against the Wheels and stop the car.

The pawl may be connected by a line, y, with the engine, so that bydrawing upon the line, the engineer can immediately apply all of thebrakes to a train, Without reference to the brakemen, the duty of thebrakemen being to again dranT the brakes from the Wheels preparatory tothe start of the train; or the brakemanto the respective cars may tripthe pawls, and thereby brin g the brakes into effective operation. Ineither case provision exists for instant and e'ective application of allof the brakes, instead of the application effected only by Winding upthe brake-chains. Weights z may be used instead of the springs, but thelsprings are preferred.

Each brake is made with an iron shoe, asin ordinary brakes; butbetweenrthe shoe and the brake-body I apply a cushion, j, of caout choucor similar elastic material or compound, which shall tend to createuniform pressure from the Whole surface of the shoe, instead of fromparts thereof, as is the case when the shoe is rigidly attached.

AInstead of connecting the brake-frames by springs placed at the outsideof the Wheels, as shown, they may be connected by a spring or springsplaced between the Wheels.

I do not claim a device in which the brakeA shoe is forced against theWheel by a spring acting indirectlyY and through intervenin g mechanismupon the brakebeain but I do claim, and desire to secure by LettersPatente In a railwaycar brake, the combination of springs u o, securedto the brake-bars h i, with lever r, rod q, chain s, and brakerod t, allsubstantially as set forth.

VJOHN nAnnrN.

Witnesses:

FRANcIs GoULn, r M. W. FROTHINGHAM.

